Set a 10-inch heavy-bottomed ovenproof pan or cast-iron skillet on a rimmed baking sheet and place both on oven rack adjusted to lower-middle position, and heat oven to 500 degrees F. When oven reaches temperature (about 15 to 20 minutes), remove skillet from oven and transfer to stove top over high heat (be careful -- pan and handle will be extremely hot).

Immediately place steaks in skillet, being carefull that they are not touching each other. Sear steaks for 2 to 3 minutes without disturbing, turn with tongs and sear second side another 2 to 3 minutes without disturbing, or until both sides are well-browned and have a nice crust. Remove skillet from heat, and using tongs, transfer steaks to hot baking sheet in oven. (After transferring steaks to oven, proceed with pan sauce.)

Roast 4 to 6 minutes for rare (red in center and warm throughout), 6 to 8 minutes for medium-rare (pinkish red in center and fairly hot), or 8 to 10 minutes for medium (pink in center, grayish brown surrounding and hot throughout). Remember, residual heat built up in steaks will continue to cook the meat until it begins to cool off, meat temperature will rise 5 to 10 degrees after it is removed from the oven. This means you should undercook your steaks, removing them from oven before they reach desired temperature.

When steaks are done to your liking, transfer to large plate. Double check doneness by thermometer (rare - 130 to 140 degrees F, medium-rare - 140 to 150 degrees F, medium - 150 to 160 degrees F), or touch (very rare feels soft and squishy, rare is soft to the touch, medium-rare yields gently to the touch, while medium yields only slightly to the touch and is beginning to firm up, and medium-well is firm to the touch). Tent steaks loosely with foil and let rest for 5 to 10 minutes, allowing steaks to finish cooking from residual heat, and meat juices to redistribute and settle before serving. Serve as individual steaks or slice just before serving on warmed plates.

Shiraz Sauce:

After transferring steaks to oven, melt 1 tablespoon butter in same skillet with fond (brown bits in pan leftover from cooking) and residual fat that it was cooked in. Add shallots and cook over medium-low heat, stirring, until translucent, about 2 to 3 minutes.

Raise heat to mediun-high, add wine, and bring to a boil. Using a wooden spoon or spatula, stir and scrap to loosen any flavorful browned bits stuck to skillet and incorporate them into sauce. When wine is almost gone, add stock, herbs (if using dry herbs, just a pinch), tomato paste and sugar, bring to a boil and cook until reaching the sauce consistency you desire. It should be thick enough to coat back of a regular spoon.

Remove from heat, whisk in remaining 2 tablespoons cold butter until melted and sauce is thickened, smooth, and glossy. Correct seasoning with salt and pepper. Stir in any accumulated juices from the steak plate. Spoon sauce over cooked steaks just before serving.